package 题目集.dfs.图;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.HashSet;
import java.util.Set;
import java.util.StringTokenizer;

//https://pintia.cn/problem-sets/1740285363143692288/exam/problems/1740285399961296905?type=7&page=0
public class ch01_深入虎穴 {
    static int[][] map;
    static boolean visited[];
    //返回该节点最远抵达的子孩子编号，和距离
    public static int[] fun(int i){
        if (visited[i]){
            return new int[]{i,-1};
        }
        if (map[i].length==0){  //叶子节点
            return new int[]{i,0};
        }
        visited[i]=true;
        int[] res={i,0};
        for (int j = 0; j < map[i].length; j++) {
            int[] fun = fun(map[i][j]);
            if (fun[1]+1>res[1]){   //更新最远距离
                res[0]=fun[0];
                res[1]=fun[1]+1;
            }
        }
        visited[i]=false;
        return res;
    }

    public static void main(String[] args) {
        Reader sc=new Reader();
        int n = sc.nextInt();
        map=new int[n+1][];
        visited=new boolean[n+1];
        Set<Integer> set=new HashSet<>();
        for (int i = 1; i <= n; i++) {
            set.add(i);
        }
        for (int i = 1; i < map.length; i++) {
            map[i]=new int[sc.nextInt()];
            for (int j = 0; j < map[i].length; j++) {
                int to = sc.nextInt();
                map[i][j]=to;
                set.remove(to);
            }
        }
        int[] res=fun(set.iterator().next());
//        int[] res={0,-1};
//        for (int i = 1; i <= n; i++) {
//            int[] fun = fun(i);
//            if (fun[1]>res[1]){
//                res=fun;
//            }
//        }
        System.out.println(res[0]);
    }
    static class Reader {
        private BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
        private StringTokenizer tokenizer = new StringTokenizer("");

        private String innerNextLine() {
            try {
                return reader.readLine();
            } catch (IOException ex) {
                return null;
            }
        }

        public boolean hasNext() {
            while (!tokenizer.hasMoreTokens()) {    //内存中没有
                String nextLine = innerNextLine();
                if (nextLine == null) {     //且没有下一行
                    return false;
                }
                tokenizer = new StringTokenizer(nextLine);  //读入一行
            }
            return true;
        }

        public String nextLine() {
            tokenizer = new StringTokenizer("");    //清空内存中的字符
            return innerNextLine();
        }

        public String next() {
            hasNext();
            return tokenizer.nextToken();
        }

        public int nextInt() {
            return Integer.parseInt(next());
        }

        public long nextLong() {
            return Long.parseLong(next());
        }

        public double nextDouble(){
            return Double.parseDouble(next());
        }
//    public BigInteger nextBigInt() {
//        return new BigInteger(next());
//    }
    }

}

